AIRCRAFT ENGINE WITH CLUTCH AND MECHANICAL LOCK

Description

TECHNICAL FIELD

[0001] The application relates generally to aircraft engines and, more particularly, to systems and methods for engaging the engines to rotatable loads.

BACKGROUND OF THE ART

[0002] In a helicopter, a clutch between an engine shaft and the helicopter rotor allows an engine to be used for other purposes than for rotating the helicopter rotor.

[0003] The conventional mechanical solution is to install an engagement device, such as a friction mechanism (e.g., like a disc(s) clutch or belt clutch) or a hydraulic coupling, to progressively engage the rotor. Such engagement devices need to be sized to transmit the maximum torque, which results in voluminous and heavy components. There is therefore a need for improvements.

[0004] A prior art aircraft assembly having the features of the preamble of claim 1 is disclosed in US 2014/373521 A1. Another prior art aircraft assembly is disclosed in EP 3 321 494 A1.

SUMMARY

[0005] In one aspect, there is provided an aircraft engine assembly as set forth in claim 1.

[0006] In yet another aspect, there is provided a method of operating an aircraft engine as set forth in claim 10.

DESCRIPTION OF THE DRAWINGS

[0007] Reference is now made to the accompanying figures in which:

Fig. 1 is a schematic view of an aircraft engine in accordance with one example;

Fig. 2 is a schematic view of an engagement device of the aircraft engine of Fig. 1 in accordance with one example;

Fig. 3 is a schematic view of an engagement device in accordance with another example and that may be used with the aircraft engine of Fig. 1

Fig. 4 is a schematic view of an engagement device, shown in a hotel operation mode, in accordance with yet another example that may be used with the aircraft engine Fig. 1; and

Fig. 5 is a schematic view of the engagement device of Fig. 4 shown in a normal operation mode.

DETAILED DESCRIPTION

[0008] Referring to Fig. 1, an aircraft engine 10 is generally shown and includes an engine 12', which is an intermittent internal combustion engine. In a particular example, the engine 12' is an internal combustion engine 12 that comprises one or more rotary units each configured for example as a Wankel engine, or one or more reciprocating pistons. The internal combustion engine 12 drives an engine shaft 14 that is used for driving a rotatable load L that is secured to an output shaft 16 of the aircraft engine 10. It is understood that the aircraft engine 10 may alternately be configured to drive any other appropriate type of load, including, but not limited to, one or more generator(s), propeller(s), accessory(ies), rotor mast(s), compressor(s), or any other appropriate type of load or combination thereof. The rotatable load L may be a helicopter rotor. The aircraft engine 10 may be used as a prime mover engine, such as on an aircraft or other vehicle, or in any other suitable application.

[0009] In a particular example, the internal combustion engine 12 is a rotary engine comprising three rotary units each configured as a Wankel engine, with a rotor cavity having a profile defining two lobes, preferably an epitrochoid, in which a rotor is received with the geometrical axis of the rotor being offset from and parallel to the axis of the rotor cavity, and with the rotor having three circumferentially-spaced apex portions and a generally triangular profile with outwardly arched sides, so as to define three rotating combustion chambers with variable volume. Alternatively, the internal combustion engine 12 may be any type of intermittent internal combustion engine such as a piston engine. Alternatively, the internal combustion engine may be replaced by any other suitable type of engine such as, an electrical motor.

[0010] In the example shown, the internal combustion engine 12 is a component of a turbo-compounded engine 100 of the aircraft engine 10; the turbo-compounded engine 100 including a compressor 18 for compressing the air before it is fed to an air inlet 12a of the internal combustion engine 12. As illustrated, the compressor 18 has an inlet 18a fluidly connected to an environment E outside of the aircraft engine 10 and an outlet 18b fluidly connected via a conduit 20a to the inlet 12a of the internal combustion engine 12 for feeding compressed air to the internal combustion engine 12.

[0011] In a particular example, the turbo-compounded engine 100 may be as described in Lents et al.'s US patent No. 7,753,036 issued July 13, 2010 or as described in Julien et al.'s US patent No. 7,775,044 issued August 17, 2010, or as described in Thomassin et al.'s U.S. patent publication No. 2015/0275749 published October 1, 2015, or as described in Bolduc et al.'s U.S. patent publication No. 2015/0275756 published October 1, 2015.

[0012] As illustrated, the turbo-compounded engine 100 includes a turbine 22 receiving the exhaust gases from the internal combustion engine 12. The turbine 22 has an inlet 22a fluidly connected via a conduit 20b to an exhaust 12b of the internal combustion engine 12. The turbine 22 has an outlet 22b fluidly connected to the environment E for expelling exhaust gases generated by the internal combustion engine 12 and after their passage in the turbine 22.

[0013] In the case of a rotary engine, the internal combustion engine 12 provides an exhaust flow of high pressure hot gas exiting at high peak velocity, in the form of exhaust pulses. The turbine 22 may comprise a single turbine, or two or more turbine stages in serial fluid communication; the two or more turbine stages may have different reaction ratios from one another and might be configured to cater to the exhaust pulses of the internal combustion engine. Other configurations are contemplated.

[0014] In the illustrated example, the compressor 18 and the turbine 22 are in a driving engagement with a gearbox 24. In the illustrated example, the compressor 18 and the turbine 22 are engaged to a same turbine shaft 22c, which is drivingly engaged to the engine shaft 14 through the gearbox 24; the turbine shaft 22c and the engine shaft 14 are parallel and radially offset from one another. Alternate configurations are possible, including, but not limited to, the rotor(s) of the compressor 18 being engaged to a shaft separate from the turbine shaft 22c (whether coaxial with the turbine shaft 22c, with the engine shaft 14, or offset from both) and in driving engagement with the turbine shaft 22c and/or the engine shaft 14, for example through the gearbox 24; and/or two or more of the shafts extending at an angle (perpendicularly or otherwise) to each other.

[0015] In the depicted example, energy from the exhaust gases exiting the internal combustion engine 12 is extracted by the turbine 22; the energy extracted by the turbine 22 being compounded with the internal combustion engine 12 to drive the engine shaft 14 via the gearbox 24.

[0016] As shown in Fig. 1, the gearbox 24 includes a plurality of gears 24a meshed with one another to transfer a rotation input between the turbine shaft 22c and the engine shaft 14. The gearbox 24 may create a rotational speed ratio between a rotational speed of the engine shaft 14 and that of the turbine shaft 22c. In other words, the gearbox 24 may increase or decrease a torque transmitted from the turbine shaft 22c to the engine shaft 14.

[0017] In some cases, it might be desired to have the internal combustion engine 12 running without having the rotatable load L (e.g., helicopter rotor) rotating. This type of configuration is referred to herein below as a hotel operation mode as opposed to a normal operation mode in which both the engine shaft 14 and the output shaft 16, and thus the rotatable load L, are in rotation.

[0018] Conventional systems such as friction clutches, may be used to bring the engine shaft 14 in driving engagement with the output shaft 16. However, such clutches need to be able to withstand a maximum torque generated by the internal combustion engine 12. For a flying vehicle, weight is always a concern. Consequently, using a conventional clutch able to withstand the maximum torque of the internal combustion engine 12 might be detrimental to the performance of the vehicle. Direct clutches, such as dog clutches, might be used. Their weights is typically less than that of conventional friction clutches for a same value of a maximum transmittable torque. However, the rotational speeds of the engine shaft 14 and that of the output shaft 16 must be equivalent prior to actuating the dog clutch to avoid damaging the system.

[0019] In the depicted example, the aircraft engine 10 further includes a brake, also referred to as a clutch 30, for selectively engaging the engine shaft 14 to the output shaft 16 and that is used for initiating rotation of the rotatable load L. The clutch 30 includes a first component 30', which is in driving engagement with the engine shaft 14, and a second component 30". The clutch 30 is operable between a first configuration and a second configuration. The engine shaft 14 rotates independently from the output shaft 16 in the first configuration. Stated otherwise, the engine shaft 14 is drivingly disengaged from the output shaft 16 in the first configuration of the clutch 30. The engine shaft 14 transmits a torque to the output shaft 16 via the clutch 30 in the second configuration of the clutch 30. The clutch 30 is operable to gradually increase a force transmitted from the engine shaft 14 and the output shaft 16 such that a magnitude of the torque transmittable from the engine shaft 14 to the output shaft 16 gradually increases from the first configuration to the second configuration. More specifically, in the first configuration of the clutch 30, the first component 30' is rotatable relative to the second component 30" and the engine shaft 14 is rotatable relative to the output shaft 16. In the second configuration of the clutch 30, the first and second components 30', 30" are engaged with one another such that rotation of the first component 30' relative to the second component 30" is limited and the engine shaft 14 rotates with the output shaft 16. The clutch is configured to selectively engage the engine shaft 14 to the output shaft 16 via the engagement between the first component 30' and the second component 30".

[0020] The clutch 30 is sized to be able to transmit a torque that corresponds to at least a minimal torque causing a rotational acceleration of the rotatable load L. In a particular embodiment, the clutch 30 is able to transmit a torque that corresponds to at least a torque able to increase a rotational speed of the output shaft 16 from rest to a given rotational speed.

[0021] The aircraft engine 10 further includes a mechanical lock 32 that is able to lock the engine shaft 14 with the output shaft 16 such that the engine shaft 14 is rotatably locked to the output shaft 16. When the engine shaft 14 is rotatably locked to the output shaft 16, the output shaft 16 and the engine shaft 14 are in joint rotation. The mechanical lock 32 is operable between a first position in which the engine shaft 14 is rotatable relative to the output shaft 16 and a second position in which the engine shaft 14 is rotatably locked to the output shaft 16 as described herein above. The engine shaft 14 and the output shaft 16 are in joint rotation in the second position of the mechanical lock 32. More specifically, in the first position, the mechanical lock is disengaged from the first component 30' of the clutch 30. In the second position, the first component 30' and the second component 30" of the clutch 30 are secured for joint rotation one relative to the other.

[0022] Herein, the expression "joint rotation" means that, rotation of a first element causes, or is caused by, rotation of a second element, whether or not they rotate at a same rotational speed. For instance, if the first element is secured to a first gear and the second element is secured to a second gear meshed with the first gear, rotation of the first element induces rotation of the second element and vice versa. The first and second gears may have different numbers of teeth such that a rotational speed ratio would be created between the first and second elements. However, herein, the first and second elements would be consider to be in joint rotation regardless of their variation in rotational speeds.

[0023] In the example shown, the mechanical lock 32 and the clutch 30 are parts of an engagement device 40. A plurality of examples of the engagement device are possible, three are described in detail herein below with reference to Figs. 1 to 5.

[0024] Referring to Figs. 1-2, the engagement device 40 further includes a gear train 34 that includes a driver sun gear 34a in driving engagement with the engine shaft 14, a driven sun gear 34b in driving engagement with the output shaft 16, planet gears 34c meshed with both of the driver sun gear 34a and the driven sun gear 34b, and a planet carrier 34d that rotatably supports the planet gears 34c.

[0025] In the first configuration of the clutch 30, rotation of the driver sun gear 34a induces rotation of the planet gears 34c that are meshed therewith and, because of the rotational inertia of the rotatable load L, the driven sun gear 34b remain substantially immobile. As a result, the planet carrier 34d rotates about an axis of rotation A that is coincident with that of the driver sun gear 34a.

[0026] To induce rotation of the driven sun gear 34b, and thus of the output shaft 16, rotation of the planet carrier 34d has to be limited. In the depicted example, the clutch 30 is used to limit rotation of the planet carrier 34d. More specifically, and as more clearly seen in Fig. 2, the planet carrier 34d defines a surface 34e on which friction may be applied to decrease a rotational speed of the planet carrier 34d and, consequently, increase that of the driven sun gear 34b. In the example shown, the surface 34e belongs to a disk 34f located on an external periphery of the planet carrier 34d; the disk 34f circumferentially extending all around the axis A. In this example, the disk 34f corresponds to the first component 30' of the clutch 30.

[0027] The clutch 30 includes a housing 30a that is secured to the aircraft such that the housing 30a is immobile. The housing 30a encloses a braking member 30b, which, in the depicted embodiment, corresponds to brake pads 30c, two in the example shown that face each other and that receive the disk 34f therebetween. The braking member 30b is operable between a free configuration in which the disk 34f and the braking member 30b are rotatable relative to one another, and a braking configuration in which the braking member 30b limits rotation of the disk 34f. The braking member 30b may be any suitable device operable to exert a force on the disk. In this example, the braking member 30b corresponds to the second component 30" of the clutch 30.

[0028] The brake pads 30c are movable within the housing 30a to be selectively in contact with the surface 34e of the disk 34f or distanced therefrom. In the second configuration of the clutch 30, the brake pads 30c exert a frictional force on the planet carrier 34d via the disk 34f when they are in contact with the surface 34e. The brake pads 30c are engaged by any suitable actuator known in the art (e.g., hydraulic, solenoid, etc).

[0029] At some point, the planet carrier 34d stops rotating. However, an increase of the rotational speed and torque of the engine shaft 14, and thus of the driver sun gear 34a, might cause the clutch 30 to "slip" and the planet carrier 34d to rotate relative to the brake pads 30c because the clutch 30 is only able to withstand a maximum torque that is less than a maximum torque of the engine 12. In other words, an acceleration of the engine shaft 14 might not translate in an acceleration of the output shaft 16 because the clutch 30 is not configured to withstand a torque beyond a given threshold. Consequently, when the planet carrier 34d stops rotating, the planet carrier 34d is locked with the mechanical lock 32 such that it remains substantially immobile regardless of the rotational speed and torque of the engine shaft 14.

[0030] Still referring to Fig. 2, the mechanical lock 32 is shown enlarged. As illustrated the housing 30a and the disk 34f of the planet carrier 34d both define a plurality of apertures 30d, 34g circumferentially distributed along their circumference; the apertures 34g of the disk 34f being registerable with the apertures 30d of the housing 30c. The mechanical lock 32 includes a rod 32a that is movable within a casing 32b secured to the housing 30a of the clutch 30; the rod 32a being slidably receivable within the apertures 30d, 34g of both of the housing 30a and the disk 34f.

[0031] When the planet carrier 34d stops rotating, the rod 32a is moved along its longitudinal axis A' through one of the apertures 30d of the housing 30 and through one of the apertures 34g of the disk 34f to prevent any further rotation of the planet carrier 34d relative to the housing 30a. In the example shown, an actuator 32c is used to move the rod 32a. The actuator 32c may be any suitable type of actuator such as a solenoid, a hydraulic actuator, etc. In a particular example, energy must be provided to the actuator 32c to move the rod out of the apertures 30d, 34g of the housing 30a and of the disk 34f from the second position to the first position. This might prevent the engine shaft 14 from becoming drivingly disengaged from the rotatable load L, which may be a helicopter rotor, when the helicopter is flying and an energy source becomes erroneously disconnected from the actuator 32c or if the actuator fails. In the example shown, the rod 32a is biased with a biasing member, such as a spring, in the apertures 30d, 34g and energy must be provided to the actuator 32c to overcome a force generated by the biasing member.

[0032] Referring now to Fig. 3, another example of the engagement device is shown at 140. For the sake of clarity, reference numerals in common to both engagement devices 40, 140 of Fig. 3 and Fig. 4 are not reproduced on Fig. 4 as the engagement device 140 is similar to the engagement device 40 described above with reference to Fig. 3. However, the rotatable load L is in driving engagement with the planet carrier 134d instead of with the driven sun gear 134b. More specifically, a gear 134h is secured to the planet carrier 134d; the gear 134h being in driving engagement with the output shaft 16. The gear 134h may be monolithic with the planet carrier 134d.

[0033] In the depicted example, as the rotatable load L is in driving engagement with the planet carrier 134d, rotation of the driver sun gear 34a translates in rotation of the driven sun gear 134b because there is more inertia to overcome on the planet carrier 134d than on the driven sun gear 134b. To start rotation of the planet carrier 134d, and of the rotatable load L, rotation of the driven sun gear 134b has to be limited.

[0034] For that purpose, the clutch 30 is operatively connected to the driven sun gear 134b. In the example shown, the driven sun gear 134b is secured to a truncated shaft 134i. The disk 134f circumferentially extends all around, and is secured to, the truncated shaft 134i. The housing 30a of the clutch 30, the brake pads 30c, and the mechanical lock 32 are as described with reference to Fig. 3. The difference being that the disk 134f is secured to the truncated shaft 134i instead of to the planet carrier 134d.

[0035] In the example depicted in Fig. 3, a rotational ratio is provided via the gear train 34 between the driver sun gear 34a and the planet carrier 134d. In a particular example, a rotational speed ratio corresponding to a rotation speed of the driver sun gear 34a over that of the planet carrier 134d is two. Other ratios may be obtained by varying teeth count of the gears of the gear train 34 as known in the art.

[0036] Referring now to Figs. 4-5, another example of an engaging device is generally shown at 240. The engaging device 240 includes a clutch 230' provided in the form of a torque converter 230 operatively coupled between the engine shaft 14 and the output shaft 16. The torque converter 230 includes an input 230a in driving engagement with the engine shaft 14 and an output 230b in driving engagement with the output shaft 16. The input 230a is drivingly engageable to the output 230b via a fluid contained in the torque converter 230. The torque converter 230 may be any torque converter known in the art. In the depicted example, the torque converter 230 includes a pump or impeller 230a₁, which may be a part of the input 230a; a turbine 230b₁, which may be a part of the output 230b; and a stator 230b₂, which may be a part of the output 230b. The stator 230b₂ is configured for redirecting the fluid exiting the turbine 230b₁ toward an inlet of the impeller 230a₁ with an appropriate incidence angle. In a particular embodiment, there is no fluid in the torque converter 230 in the first configuration of the clutch 230' such that the input 230a and the output 230b of the torque converter 230 are rotatable one relative to the other. In the second configuration of the clutch 230', fluid is present in the torque converter 230 such that a torque is transmittable via the fluid from the input 230a to the output 230b of the torque converter 230.

[0037] In the depicted example, a first component 230" of the clutch 230' corresponds to the input 230a of the torque converter 230 and the second component 230‴ of the clutch 230' is engaged to the output 230b of the torque converter 230. More specifically, the second component 230‴ of the clutch 230' corresponds to the turbine 230b₁ of the torque converter 230; the turbine 230b₁ of the torque converter 230 being engaged to the output shaft 16.

[0038] The torque converter 230 transmits a torque from the engine shaft 14 to the output shaft 16 via a cooperation of the input 230a and the output 230b. At some point, the rotational speed of the engine shaft 14 corresponds to that of the output shaft 16 and the engine shaft 14 may be locked with the output 16 shaft via the mechanical lock 232'.

[0039] In the present example, the mechanical lock 232' is a dog clutch 232 having a first part 232a in driving engagement with the input 230a of the torque converter 230 and a second part 232b in driving engagement with the output shaft 16. As illustrated on Fig. 5, one of the first part and the second part 232a, 232b has male members 232c, such as pins, and the other of the first part and the second part 232a, 232b has female members 232d, such as apertures correspondingly shaped to receive the male members 232c in the second position (Fig. 5) of the mechanical lock 232'. An actuator 232e, that may be any kind of actuators described above, is used to move the first and second parts 232a, 232b toward each other to mate the male members 232c with the female members 232d when the engine shaft 14 rotates at substantially the same speed than that of the output shaft 16.

[0040] The first and second parts 232a, 232b of the dog clutch 232 may be biased in a position where they are engaged with one another. A biasing member B, such as a spring, may exert a force on at least one of the first and second parts 232a, 232b to maintain them engaged up to a point where energy is provided to the actuator 232e to move the first and second parts 232a, 232b away from each other to disengage them.

[0041] In a particular example, the torque converter 230 may be replaced by a magnetic clutch. In a particular example, the clutch 30 described with reference to Figs. 1-4 may use a magnetic field to transmit the torque rather than friction.

[0042] In a particular example, the combination of the clutch and the mechanical lock allows to start rotation of the rotatable load while having the internal combustion engine already in operation. The overall weight of the disclosed aircraft engine is less than that of a configuration in which only a clutch sized to withstand the maximal torque of the internal combustion engine is used for equal power.

[0043] In a particular example, the power required to accelerate the rotatable load from rest to idle remains small if a sufficient period of time is allowed for accelerating the rotatable load. In a particular example, the period of time varies from 15 to 30 seconds. In a particular example, initial calculations shows that power for engaging the rotatable load via the drive train 34 can be a small fraction of the internal combustion engine 12 nominal output and may be below 10% of the engine nominal output. This might allow for the reduction of the volume and weight of the clutch. In a particular example, the addition of mechanical lock adds a little weight, but can still be controlled within acceptable limits, since simple feature like sliding pins, dogs or splines can take heavy loads in small and light packages. In a particular example, the progressive engagement and lock can be achieved with non-rotating components, keeping simplicity and improving the reliability and maintainability of the system.

[0044] To operate the aircraft engine 10, the engine shaft 14 is rotated. Rotation of the rotatable load L is started by progressively increasing a magnitude of a torque transmitted from the engine shaft 14 to the output shaft 16 in driving engagement with the rotatable load L. When the rotatable load L reaches a given rotational speed, the output shaft 16 is locked to the engine shaft 14 such that the output shaft 16 and the engine shaft 14 are in joint rotation. At that point, the rotational speed of the rotatable load L is increased beyond the given rotational speed.

[0045] In the depicted example, starting rotation of the rotatable load L includes: rotating the driver sun gear 34a thereby rotating one of the driven sun gear 34b and the planet carrier 34d rotatably supporting the planet gears 34c; the output shaft 16 being in driving engagement with the other of the driven sun gear 34b and the planet carrier 34d. And, rotation of the one of the driven sun gear 34b and the planet carrier 34d is decelerated such that rotation of the other of the driven sun gear 34b and the planet carrier 34d is accelerated.

[0046] As illustrated on Figs. 3 and 4, decelerating the one of the driven sun gear 34b and the planet carrier 34d includes exerting a force on the one of the driven sun gear 34b and the planet carrier 34d. In the example shown, the force on the one of the driven sun gear 34b and the planet carrier 34d is a friction force exerted on a surface 34e of the one of the driven sun gear 34b and the planet carrier 34d.

[0047] In the example shown, locking the output shaft 16 to the engine shaft 14 includes operating the mechanical lock 32 from the first position in which the engine shaft 14 is rotatable relative to the output shaft 16 to the second position in which the engine shaft 14 is rotatably locked to the output shaft 16. The engine shaft 14 and the output shaft 16 are in joint rotation with each other in the second position of the mechanical lock 32. As shown, operating the mechanical lock 32 includes moving the rod 32a with the actuator 32c engaged to the rod 32a.

Claims

1. An aircraft engine assembly (100) comprising:

an engine (12) having an engine shaft (14);

an output shaft (16);

a clutch (30; 230) in driving engagement between the engine shaft (14) and the output shaft (16), the clutch (30; 230) having a first component (34f; 230a) in driving engagement with the engine shaft (14) and a second component (30b; 230b₁), the clutch (30; 230) operable between a first configuration and a second configuration, in the first configuration the first component (34f; 230a) is rotatable relative to the second component (30b; 230bi) and the engine shaft (14) is rotatable relative to the output shaft (16), in the second configuration the first and second components (34f, 30b; 230a, 230bi) are engaged with one another such that rotation of the first component (34f) relative to the second component (30b) is limited and the engine shaft (14) rotates with the output shaft (16), the clutch (30; 230) configured to selectively engage the engine shaft (14) to the output shaft (16) via the engagement between the first component (34f; 230a) and the second component (30b; 230b₁);

a mechanical lock (32; 232) operable between a first position and a second position, in the first position the mechanical lock (32; 232) is disengaged from the first component (34f; 230a) of the clutch (30; 230), and in the second position the first component (34f; 230a) and the second component (30b; 230b₁) of the clutch (30; 230) are secured for joint rotation one relative to the other,

characterised in that:
the aircraft engine assembly (100) further comprises a turbine (22) having a turbine shaft (22c) drivingly engaged to the engine shaft (14), the turbine having a turbine inlet (22a) fluidly connected to an exhaust (12b) of the engine (12), wherein the engine (12) is an intermittent internal combustion engine (12) and the output shaft (16) is operatively connectable to a rotatable load (L).

2. The aircraft engine assembly of claim 1, further comprising a gear train (34) including a driver sun gear (34a) secured to the engine shaft (14), a driven sun gear (34b; 134b), planet gears (34c) meshed with both of the driver sun gear (34a) and the driven sun gear (34b; 134b), and a planet carrier (34d; 134d) rotatably supporting the planet gears (34c), the output shaft (16) drivingly engaged to one of the driven sun gear (34b; 134b) and the planet carrier (34d; 134d), the other of the driven sun gear (34b; 134b) and the planet carrier (34d; 134d) rotating upon rotation of the engine shaft (14) in the first configuration of the clutch (30; 230), rotation of the other of the driven sun gear (34b; 134b) and the planet carrier (34d; 134d) limited by the clutch (30; 230) in the second configuration of the clutch (30; 230).

3. The aircraft engine assembly of claim 2, wherein the first component (34f) of the clutch (30) is a disk (34f) secured to the other of the driven sun gear (34b; 134b) and the planet carrier (34d; 134d), the second component (30b) of the clutch (30) being a braking member (30b) operable between a free configuration in which the disk (34f) and the braking member (30b) are rotatable relative to one another and a braking configuration in which the braking member limits rotation of the disk (34f) relative to the braking member (30b).

4. The aircraft engine assembly of claim 3, wherein the braking member (30b) includes braking pads (30c) receiving the disk (34f) therebetween, the brake pads (30c) in contact with the disk (34f) in the braking configuration for limiting rotation of the disk (34f) by friction.

5. The aircraft engine assembly of claim 1, wherein the clutch (230) is a torque converter (230), the first component (230a) being an input (230a) of the torque converter (230) in driving engagement with the engine shaft (14) and the second component (230b₁) being engaged to an output (230b) of the torque converter (230), the output (230b) in driving engagement with the output shaft (16), the input (230a) drivingly engageable to the output (230b) via a fluid contained in the torque converter (230), the mechanical lock (232') engaging the engine shaft (14) with the output (230b) of the torque converter (230) in the second position of the mechanical lock (232').

6. The aircraft engine assembly of claim 5, wherein the mechanical lock (232) is a dog clutch (232) having a first part (232a) in driving engagement with the input (230a) of the torque converter (230) and a second part (232b) in driving engagement with the output shaft (16), one of the first part (232a) and the second part (232b) having male members (232c) and the other of the first part (232a) and the second part (232b) having female members (232d) engaged by the male members (232c) in the second position of the mechanical lock (232').

7. The aircraft engine assembly of any preceding claim, wherein the mechanical lock (32; 232) includes a rod (32a) and an actuator (32c) engaged to the rod (32a), the actuator (32c) operable to move the rod (32a) between the first and second positions of the mechanical lock (32; 232), optionally wherein the actuator is a solenoid.

8. The aircraft engine assembly of claim 7, wherein a de-energized position of the mechanical lock (32; 232) corresponds to the second position.

9. The aircraft engine assembly of any preceding claim, wherein the engine (12) is a rotary engine.

10. A method of operating an aircraft engine (12) comprising:

rotating an engine shaft (14) of an engine (12) ;

starting rotation of a rotatable load (L) by progressively increasing a magnitude of a torque transmitted from the engine shaft (14) to an output shaft (16) in driving engagement with the rotatable load (L);

when the rotatable load (L) reaches a given rotational speed, locking the output shaft (16) to the engine shaft (14); and

increasing a rotational speed of the rotatable load (L) beyond the given rotational speed,

characterised in that:
the aircraft engine (12) comprises a turbine (22) having a turbine shaft (22c) drivingly engaged to the engine shaft (14), the turbine having a turbine inlet (22a) fluidly connected to an exhaust (12b) of the engine (12), wherein the engine (12) is an intermittent internal combustion engine (12) and the output shaft (16) is operatively connectable to a rotatable load (L).

11. The method of claim 10, wherein starting rotation of the rotatable load (L) includes:

rotating a driver sun gear (34a) in driving engagement with the engine shaft (14) thereby rotating one of a driven sun gear (34b; 134b) and a planet carrier (34d; 134d) rotatably supporting planet gears (34c) meshed with the driver sun gear (34a) and the driven sun gear (34b; 134b), the output shaft (16) in driving engagement with the other of the driven sun gear (34b; 134b) and the planet carrier (34d; 134d); and

decelerating rotation of the one of the driven sun gear (34b; 134b) and the planet carrier (34d; 134d) thereby accelerating rotation of the other of the driven sun gear (34b; 134b) and the planet carrier (34d; 134d).

12. The method of claim 11, wherein decelerating the one of the driven sun gear (34b; 134b) and the planet carrier (34d; 134d) includes exerting a force on the one of the driven sun gear (34b; 134b) and the planet carrier (34d; 134d).

13. The method of claim 12, wherein exerting a force on the one of the driven sun gear (34b; 134b) and the planet carrier (34d; 134d) includes exerting a friction force on a surface (34e) of the one of the driven sun gear (34b; 134b) and the planet carrier (34d; 134d).

14. The method of any of claims 10 to 13, wherein locking the output shaft (16) to the engine shaft (14) includes operating a mechanical lock (32; 232) from a first position in which the engine shaft (14) is rotatable relative to the output shaft (16) to a second position in which the engine shaft (14) is rotatably locked to the output shaft (16), the engine shaft (14) and the output shaft (16) in joint rotation with each other in the second position of the mechanical lock (32; 232).

15. The method of claim 14, wherein operating the mechanical lock (32; 232) includes moving a rod (32a) with an actuator (32c) engaged to the rod (32a).

Ansprüche

1. Luftfahrzeugtriebwerksbaugruppe (100), umfassend:

ein Triebwerk (12), das eine Triebwerkswelle (14) aufweist;

eine Ausgangswelle (16);

eine Kupplung (30; 230) in Antriebseingriff zwischen der Triebwerkswelle (14) und der Ausgangswelle (16), wobei die Kupplung (30; 230) eine erste Komponente (34f; 230a) in Antriebseingriff mit der Triebwerkswelle (14) und eine zweite Komponente (30b; 230b₁) aufweist, wobei die Kupplung (30; 230) zwischen einer ersten Konfiguration und einer zweiten Konfiguration bedienbar ist, wobei in der ersten Konfiguration die erste Komponente (34f; 230a) relativ zu der zweiten Komponente (30b; 230b₁) drehbar ist und die Triebwerkswelle (14) relativ zu der Ausgangswelle (16) drehbar ist, wobei in der zweiten Konfiguration die erste und die zweite Komponente (34f, 30b; 230a, 230b₁) miteinander in Eingriff genommen sind, sodass Drehung der ersten Komponente (34f) relativ zu der zweiten Komponente (30b) begrenzt ist und sich die Triebwerkswelle (14) mit der Ausgangswelle (16) dreht, wobei die Kupplung (30; 230) konfiguriert ist, um die Triebwerkswelle (14) mit der Ausgangswelle (16) über den Eingriff zwischen der ersten Komponente (34f; 230a) und der zweiten Komponente (30b; 230b₁) selektiv in Eingriff zu nehmen;

ein mechanisches Schloss (32; 232), das zwischen einer ersten Position und einer zweiten Position bedienbar ist, wobei in der ersten Position das mechanische Schloss (32; 232) von der ersten Komponente (34f; 230a) der Kupplung (30; 230) gelöst ist und in der zweiten Position die erste Komponente (34f; 230a) und die zweite Komponente (30b; 230b₁) der Kupplung (30; 230) für gemeinsame Drehung relativ zueinander befestigt sind, dadurch gekennzeichnet, dass:
die Luftfahrzeugtriebwerksbaugruppe (100) ferner eine Turbine (22) umfasst, die eine Turbinenwelle (22c) aufweist, die antreibend mit der Triebwerkswelle (14) in Eingriff genommen ist, wobei die Turbine einen Turbineneinlass (22a) aufweist, der fluidisch mit einem Auslass (12b) des Triebwerks (12) verbunden ist, wobei das Triebwerk (12) ein intermittierender Verbrennungsmotor (12) ist und die Ausgangswelle (16) mit einer drehbaren Last (L) wirkverbunden werden kann.

2. Luftfahrzeugtriebwerksbaugruppe nach Anspruch 1, ferner umfassend einen Getriebezug (34), der ein antreibendes Sonnengetriebe (34a), das an der Triebwerkswelle (14) befestigt ist, ein angetriebenes Sonnengetriebe (34b; 134b), Planetengetriebe (34c) vernetzt sowohl mit dem antreibenden Sonnengetriebe (34a) als auch dem angetriebenen Sonnengetriebe (34b; 134b) und einen Planetenträger (34d; 134d) beinhaltet, der die Planetengetriebe (34c) drehbar stützt, wobei die Ausgangswelle (16) antreibend mit einem von dem angetriebenen Sonnengetriebe (34b; 134b) und dem Planetenträger (34d; 134d) in Eingriff genommen ist, wobei sich das andere von dem angetriebenen Sonnengetriebe (34b; 134b) und dem Planetenträger (34d; 134d) bei Drehung der Triebwerkswelle (14) in der ersten Konfiguration der Kupplung (30; 230) dreht, wobei Drehung des anderen von dem angetriebenen Sonnengetriebe (34b; 134b) und dem Planetenträger (34d; 134d) durch die Kupplung (30; 230) in der zweiten Konfiguration der Kupplung (30; 230) begrenzt ist.

3. Luftfahrzeugtriebwerksbaugruppe nach Anspruch 2, wobei die erste Komponente (34f) der Kupplung (30) eine Scheibe (34f) ist, die an dem anderen von dem angetriebenen Sonnengetriebe (34b; 134b) und dem Planetenträger (34d; 134d) befestigt ist, wobei die zweite Komponente (30b) der Kupplung (30) ein Bremselement (30b) ist, das zwischen einer freien Konfiguration, in der die Scheibe (34f) und das Bremselement (30b) relativ zueinander drehbar sind, und einer Bremskonfiguration, in der das Bremselement Drehung der Scheibe (34f) relativ zu dem Bremselement (30b) begrenzt, bedienbar ist.

4. Luftfahrzeugtriebwerksbaugruppe nach Anspruch 3, wobei das Bremselement (30b) Bremskissen (30c) beinhaltet, die die Scheibe (34f) dazwischen aufnehmen, wobei die Bremskissen (30c) in Kontakt mit der Scheibe (34f) in der Bremskonfiguration sind, um Drehung der Scheibe (34f) durch Reibung zu begrenzen.

5. Luftfahrzeugtriebwerksbaugruppe nach Anspruch 1, wobei die Kupplung (230) ein Drehmomentwandler (230) ist, wobei die erste Komponente (230a) ein Eingang (230a) des Drehmomentwandlers (230) in Antriebseingriff mit der Triebwerkswelle (14) ist und die zweite Komponente (230b₁) mit einem Ausgang (230b) des Drehmomentwandlers (230) in Eingriff genommen ist, wobei der Ausgang (230b) in Antriebseingriff mit der Ausgangswelle (16) ist, wobei der Eingang (230a) über ein Fluid, das in dem Drehmomentwandler (230) enthalten ist, antreibend mit dem Ausgang (230b) in Eingriff bringbar ist, wobei das mechanische Schloss (232') die Triebwerkswelle (14) mit dem Ausgang (230b) des Drehmomentwandlers (230) in der zweiten Position des mechanischen Schlosses (232') in Eingriff nimmt.

6. Luftfahrzeugtriebwerksbaugruppe nach Anspruch 5, wobei das mechanische Schloss (232) eine Hundekupplung (232) ist, die einen ersten Teil (232a) in Antriebseingriff mit dem Eingang (230a) des Drehmomentwandlers (230) und einen zweiten Teil (232b) in Antriebseingriff mit der Ausgangswelle (16) aufweist, wobei einer von dem ersten Teil (232a) und dem zweiten Teil (232b) männliche Elemente (232c) aufweist und der andere von dem ersten Teil (232a) und dem zweiten Teil (232b) weibliche Elemente (232d) aufweist, die durch die männlichen Elemente (232c) in der zweiten Position des mechanischen Schlosses (232') in Eingriff genommen sind.

7. Luftfahrzeugtriebwerksbaugruppe nach einem vorhergehenden Anspruch, wobei das mechanische Schloss (32; 232) eine Stange (32a) und einen Aktuator (32c) beinhaltet, der mit der Stange (32a) in Eingriff genommen ist, wobei der Aktuator (32c) bedienbar ist, um die Stange (32a) zwischen der ersten und der zweiten Position des mechanischen Schlosses (32; 232) zu bewegen, wobei optional der Aktuator ein Solenoid ist.

8. Luftfahrzeugtriebwerksbaugruppe nach Anspruch 7, wobei eine entregte Position des mechanischen Schlosses (32; 232) der zweiten Position entspricht.

9. Luftfahrzeugtriebwerksbaugruppe nach einem vorhergehenden Anspruch, wobei das Triebwerk (12) ein Drehtriebwerk ist.

10. Verfahren zum Betreiben eines Luftfahrzeugtriebwerks (12), umfassend:

Drehen einer Triebwerkswelle (14) eines Triebwerks (12);

Starten der Drehung einer drehbaren Last (L) durch progressives Erhöhen einer Größe eines Drehmoments, das von der Triebwerkswelle (14) an eine Ausgangswelle (16) in Antriebseingriff mit der drehbaren Last (L) übertragen wird;

wenn die drehbare Last (L) eine gegebene Drehgeschwindigkeit erreicht, Verriegeln der Ausgangswelle (16) an der Triebwerkswelle (14); und

Erhöhen einer Drehgeschwindigkeit der drehbaren Last (L) über die gegebene Drehgeschwindigkeit hinaus,

dadurch gekennzeichnet, dass:
das Luftfahrzeugtriebwerk (12) eine Turbine (22) umfasst, die eine Turbinenwelle (22c) aufweist, die antreibend mit der Triebwerkswelle (14) in Eingriff genommen ist, wobei die Turbine einen Turbineneinlass (22a) aufweist, der fluidisch mit einem Auslass (12b) des Triebwerks (12) verbunden ist, wobei das Triebwerk (12) ein intermittierender Verbrennungsmotor (12) ist und die Ausgangswelle (16) mit einer drehbaren Last (L) wirkverbunden werden kann.

11. Verfahren nach Anspruch 10, wobei das Starten der Drehung der drehbaren Last (L) Folgendes beinhaltet:

Drehen eines antreibenden Sonnengetriebes (34a) in Antriebseingriff mit der Triebwerkswelle (14), wodurch eines von einem angetriebenen Sonnengetriebe (34b; 134b) und einem Planetenträger (34d; 134d) gedreht wird, der Planetengetriebe (34c) vernetzt mit dem antreibenden Sonnengetriebe (34a) und dem angetriebenen Sonnengetriebe (34b; 134b) drehbar stützt, wobei die Ausgangswelle (16) in Antriebseingriff mit dem anderen von dem angetriebenen Sonnengetriebe (34b; 134b) und dem Planetenträger (34d; 134d) ist; und

Entschleunigen von Drehung von dem einen von dem angetriebenen Sonnengetriebe (34b; 134b) und dem Planetenträger (34d; 134d), wodurch Drehung des anderen von dem angetriebenen Sonnengetriebe (34b; 134b) und dem Planetenträger (34d; 134d) beschleunigt wird.

12. Verfahren nach Anspruch 11, wobei das Entschleunigen des einen von dem angetriebenen Sonnengetriebe (34b; 134b) und dem Planetenträger (34d; 134d) das Ausüben einer Kraft an dem einen von dem angetriebenen Sonnengetriebe (34b; 134b) und dem Planetenträger (34d; 134d) beinhaltet.

13. Verfahren nach Anspruch 12, wobei das Ausüben einer Kraft an dem einen von dem angetriebenen Sonnengetriebe (34b; 134b) und dem Planetenträger (34d; 134d) das Ausüben einer Reibungskraft an einer Oberfläche (34e) von dem einen von dem angetriebenen Sonnengetriebe (34b; 134b) und dem Planetenträger (34d; 134d) beinhaltet.

14. Verfahren nach einem der Ansprüche 10 bis 13, wobei das Verriegeln der Ausgangswelle (16) an der Triebwerkswelle (14) das Betätigen eines mechanischen Schlosses (32; 232) von einer ersten Position, in der die Triebwerkswelle (14) relativ zu der Ausgangswelle (16) drehbar ist, zu einer zweiten Position beinhaltet, in der die Triebwerkswelle (14) drehbar an der Ausgangswelle (16) verriegelt ist, wobei die Triebwerkswelle (14) und die Ausgangswelle (16) in gemeinsamer Drehung zueinander in der zweiten Position des mechanischen Schlosses (32; 232) sind.

15. Verfahren nach Anspruch 14, wobei das Betätigen des mechanischen Schlosses (32; 232) das Bewegen einer Stange (32a) mit einem Aktuator (32c) beinhaltet, der mit der Stange (32a) in Eingriff genommen ist.

Revendications

1. Ensemble moteur d'aéronef (100), comprenant :

un moteur (12) ayant un arbre de moteur (14) ;

un arbre de sortie (16) ;

un embrayage (30 ; 230) en prise d'entraînement entre l'arbre de moteur (14) et l'arbre de sortie (16), l'embrayage (30 ; 230) ayant un premier composant (34f ; 230a) en prise d'entraînement avec l'arbre de moteur (14) et un second composant (30b ; 230b₁), l'embrayage (30 ; 230) pouvant fonctionner entre une première configuration et une seconde configuration, dans la première configuration le premier composant (34f ; 230a) peut tourner par rapport au second composant (30b ; 230b₁) et l'arbre de moteur (14) peut tourner par rapport à l'arbre de sortie (16), dans la seconde configuration, les premier et second composants (34f, 30b ; 230a, 230b₁) sont en prise l'un avec l'autre de sorte que la rotation du premier composant (34f) par rapport au second composant (30b) est limitée et l'arbre de moteur (14) tourne avec l'arbre de sortie (16), l'embrayage (30 ; 230) étant conçu pour mettre en prise sélectivement l'arbre de moteur (14) avec l'arbre de sortie (16) par le biais de la mise en prise entre le premier composant (34f ; 230a) et le second composant (30b ; 230b₁) ;

un verrouillage mécanique (32 ; 232) pouvant fonctionner entre une première position et une seconde position, dans la première position le verrouillage mécanique (32; 232) est désengagé du premier composant (34f ; 230a) de l'embrayage (30 ; 230), et dans la seconde position, le premier composant (34f ; 230a) et le second composant (30b ; 230b₁) de l'embrayage (30 ; 230) sont fixés pour une rotation conjointe l'un par rapport à l'autre, caractérisé en ce que :
l'ensemble moteur d'aéronef (100) comprend en outre une turbine (22) ayant un arbre de turbine (22c) en prise d'entraînement avec l'arbre de moteur (14), la turbine ayant une entrée de turbine (22a) reliée fluidiquement à un échappement (12b) du moteur (12), dans lequel le moteur (12) est un moteur à combustion interne intermittent (12) et l'arbre de sortie (16) peut être relié de manière fonctionnelle à une charge rotative (L) .

2. Ensemble moteur d'aéronef selon la revendication 1, comprenant en outre un train d'engrenages (34) comportant une roue solaire d'entraînement (34a) fixée à l'arbre de moteur (14), une roue solaire entraînée (34b ; 134b), des engrenages planétaires (34c) engrenés avec à la fois la roue solaire d'entraînement (34a) et la roue solaire entraînée (34b ; 134b), et un porte-satellites (34d; 134d) supportant en rotation les engrenages planétaires (34c), l'arbre de sortie (16) étant mis en prise par entraînement avec l'un de la roue solaire entraînée (34b; 134b) et du porte-satellites (34d ; 134d), l'autre de la roue solaire entraînée (34b; 134b) et du porte-satellites (34d ; 134d) tournant lors de la rotation de l'arbre de moteur (14) dans la première configuration de l'embrayage (30 ; 230), la rotation de l'autre de la roue solaire entraînée (34b ; 134b) et du porte-satellites (34d ; 134d) étant limitée par l'embrayage (30 ; 230) dans la seconde configuration de l'embrayage (30 ; 230).

3. Ensemble moteur d'aéronef selon la revendication 2, dans lequel le premier composant (34f) de l'embrayage (30) est un disque (34f) fixé à l'autre de la roue solaire entraînée (34b ; 134b) et du porte-satellites (34d; 134d), le second composant (30b) de l'embrayage (30) étant un élément de freinage (30b) pouvant fonctionner entre une configuration libre dans laquelle le disque (34f) et l'élément de freinage (30b) peuvent tourner l'un par rapport à l'autre et une configuration de freinage dans laquelle l'élément de freinage limite la rotation du disque (34f) par rapport à l'élément de freinage (30b).

4. Ensemble moteur d'aéronef selon la revendication 3, dans lequel l'élément de freinage (30b) comporte des plaquettes de freinage (30c) recevant le disque (34f) entre elles, les plaquettes de frein (30c) étant en contact avec le disque (34f) dans la configuration de freinage pour limiter la rotation du disque (34f) par friction.

5. Ensemble moteur d'aéronef selon la revendication 1, dans lequel l'embrayage (230) est un convertisseur de couple (230), le premier composant (230a) étant une entrée (230a) du convertisseur de couple (230) en prise d'entraînement avec l'arbre de moteur (14) et le second composant (230b₁) étant en prise avec une sortie (230b) du convertisseur de couple (230), la sortie (230b) étant en prise d'entraînement avec l'arbre de sortie (16), l'entrée (230a) pouvant être mise en prise par entraînement avec la sortie (230b) par l'intermédiaire d'un fluide contenu dans le convertisseur de couple (230), le verrouillage mécanique (232') mettant en prise l'arbre de moteur (14) avec la sortie (230b) du convertisseur de couple (230) dans la seconde position du verrouillage mécanique (232').

6. Ensemble moteur d'aéronef selon la revendication 5, dans lequel le verrouillage mécanique (232) est un embrayage à crabots (232) ayant une première partie (232a) en prise d'entraînement avec l'entrée (230a) du convertisseur de couple (230) et une seconde partie (232b) en prise d'entraînement avec l'arbre de sortie (16), l'une de la première partie (232a) et de la seconde partie (232b) ayant des éléments mâles (232c) et l'autre de la première partie (232a) et de la seconde partie (232b) ayant des éléments femelles (232d) mis en prise par les éléments mâles (232c) dans la seconde position du verrouillage mécanique (232').

7. Ensemble moteur d'aéronef selon une quelconque revendication précédente, dans lequel le verrouillage mécanique (32 ; 232) comporte une tige (32a) et un actionneur (32c) en prise avec la tige (32a), l'actionneur (32c) pouvant fonctionner pour déplacer la tige (32a) entre les première et seconde positions du verrouillage mécanique (32 ; 232), éventuellement dans lequel l'actionneur est un solénoïde.

8. Ensemble moteur d'aéronef selon la revendication 7, dans lequel une position hors tension du verrouillage mécanique (32 ; 232) correspond à la seconde position.

9. Ensemble moteur d'aéronef selon une quelconque revendication précédente, dans lequel le moteur (12) est un moteur rotatif.

10. Procédé de fonctionnement d'un moteur d'aéronef (12) comprenant :

la rotation d'un arbre de moteur (14) d'un moteur (12) ;

le démarrage de la rotation d'une charge rotative (L) en augmentant progressivement une amplitude d'un couple transmis de l'arbre de moteur (14) à un arbre de sortie (16) en prise d'entraînement avec la charge rotative (L) ;

lorsque la charge rotative (L) atteint une vitesse de rotation donnée, le verrouillage de l'arbre de sortie (16) sur l'arbre de moteur (14) ; et

l'augmentation d'une vitesse de rotation de la charge rotative (L) au-delà de la vitesse de rotation donnée,

caractérisé en ce que :
le moteur d'aéronef (12) comprend une turbine (22) ayant un arbre de turbine (22c) en prise d'entraînement avec l'arbre de moteur (14), la turbine ayant une entrée de turbine (22a) reliée fluidiquement à un échappement (12b) du moteur (12), dans lequel le moteur (12) est un moteur (12) à combustion interne intermittent et l'arbre de sortie (16) peut être relié de manière fonctionnelle à une charge rotative (L).

11. Procédé selon la revendication 10, dans lequel le démarrage de la rotation de la charge rotative (L) comporte :

la rotation d'une roue solaire d'entraînement (34a) en prise d'entraînement avec l'arbre de moteur (14) faisant ainsi tourner l'un d'une roue solaire entraînée (34b ; 134b) et d'un porte-satellites (34d ; 134d) supportant en rotation des engrenages planétaires (34c) engrenés avec la roue solaire d'entraînement (34a) et la roue solaire entraînée (34b ; 134b), l'arbre de sortie (16) en prise d'entraînement avec l'autre de la roue solaire entraînée (34b ; 134b) et du porte-satellites (34d ; 134d) ; et

la décélération de la rotation de l'un de la roue solaire entraînée (34b; 134b) et du porte-satellites (34d ; 134d) accélérant ainsi la rotation de l'autre de la roue solaire entraînée (34b ; 134b) et du porte-satellites (34d ; 134d).

12. Procédé selon la revendication 11, dans lequel la décélération de l'un de la roue solaire entraînée (34b ; 134b) et du porte-satellites (34d ; 134d) comporte l'exercice d'une force sur l'un de la roue solaire entraînée (34b ; 134b) et du porte-satellites (34d ; 134d).

13. Procédé selon la revendication 12, dans lequel l'exercice d'une force sur l'un de la roue solaire entraînée (34b ; 134b) et du porte-satellites (34d ; 134d) comporte l'exercice d'une force de frottement sur une surface (34e) de l'un de la roue solaire entraînée (34b ; 134b) et du porte-satellites (34d ; 134d).

14. Procédé selon l'une quelconque des revendications 10 à 13, dans lequel le verrouillage de l'arbre de sortie (16) sur l'arbre de moteur (14) comporte l'actionnement d'un verrouillage mécanique (32 ; 232) d'une première position dans laquelle l'arbre de moteur (14) peut tourner par rapport à l'arbre de sortie (16) vers une seconde position dans laquelle l'arbre de moteur (14) est verrouillé en rotation sur l'arbre de sortie (16), l'arbre de moteur (14) et l'arbre de sortie (16) étant en rotation conjointe l'un avec l'autre dans la seconde position du verrouillage mécanique (32 ; 232).

15. Procédé selon la revendication 14, dans lequel l'actionnement du verrouillage mécanique (32 ; 232) comporte le déplacement d'une tige (32a) avec un actionneur (32c) mis en prise avec la tige (32a).

Drawing